Preparation method of solid catalyst for propylene polymerization and catalyst prepared thereby

ABSTRACT

Disclosed are a method for preparing a solid catalyst for propylene polymerization and a catalyst prepared thereby. Specifically, disclosed are a method for preparing a solid catalyst for propylene polymerization which can prepare polypropylene having excellent stereoregularity with a high production yield by using silane compounds and bicycloalkanedicarboxylate or bicycloalkenedicarboxylate as an internal electron donor, and a catalyst prepared thereby method for preparing polypropylene using the same.

TECHNICAL FIELD

The present invention is directed to a solid catalyst for propylenepolymerization, which comprises titanium, magnesium, halogen and aninternal electron donor mixture of non-aromatic compounds, and a methodfor preparing polypropylene using the same.

BACKGROUND OF THE INVENTION

Polypropylene has various industrial applications, particularly it iswidely applied for materials used in automobiles and electronicproducts, etc. with various usages. For more expanded applications ofpolypropylene, an improvement in rigidity which may be led by anincrease in the degree of crystallinity is further required.

In order to obtain such properties in polypropylene, it is needed for asolid catalyst for preparing the same to be designed to have highstereoregularity and wide molecular weight distribution.

For polymerization of olefins such as propylene or the like, a solidcatalyst comprising magnesium, titanium, an internal electron donor andhalogen as essential elements is known in this field of art, and methodsfor polymerizing or copolymerizing olefins have been proposed many.However, such methods are not satisfying in terms of obtaining polymershaving high stereoregularity with a high production yield, and thusneeded to be improved in the above aspect.

Silane compounds are usually used as an external electron donor forpreventing the stereoregularity from being deteriorated by the releaseof an internal electron donor from the reaction between a catalystcomponent and an organoaluminum in propylene polymerization. These maybe used for the improvement of bulk density or for inhibiting fineparticle generation in catalyst preparation, however the use thereof forthe improvement in activity and stereoregularity in catalyst preparationhas never known in this field of art.

In the meantime, In order to reduce the production cost by increasingthe polymerization activity and improve physical properties of theresulted polymers by improving the catalyst performance such asstereoregularity, it is generally known in this field of art to usediester of aromatic dicarboxylic acid as an internal electron donor andrelated patent applications have been filed many, for examples, U.S.Pat. Nos. 4,562,173, 4,981,930, Korean Patent No. 0072844 and the like.The above patents describe a method for preparing a catalyst showinghigh activity and stereoregularity by using aromatic dialkyldiesters oraromatic monoalkylmonoesters.

The methods according to the above-mentioned patents cannot providesatisfying high stereoregular polymers with a high yield and thusfurther improvements in the methods are required.

Korean Patent No 0491387 discloses a preparation method for a catalystusing a non-aromatic diether as an internal electron donor; KoreanPatent No. 0572616 discloses a preparation method for a catalyst using anon-aromatic compound containing both ketone and ether groups as aninternal electron donor, however both of said methods are needed to besignificantly improved in terms of the activity and stereoregularity.

SUMMARY OF THE INVENTION

The present invention has now been developed to solve the above problemsof prior art. Therefore, the purpose of the present invention is toprovide a method for preparing a solid catalyst which can producepolypropylene having excellent stereoregularity by using a silanecompound and a bicycloalkane dicarboxylate or bicycloalkendicarboxylateas an internal electron donor.

DETAILED DESCRIPTION OF THE INVENTION

In order to achieve the purpose of the present invention, the presentinvention is to provide a method for preparing a solid catalyst forpropylene polymerization comprising the following steps:

-   -   (1) reacting dialkoxy magnesium with silane compounds in the        presence of an organic solvent;    -   (2) reacting titanium halide with the resulted product obtained        from the step (1)    -   (3) adding one or more internal electron donors to the product        resulted from the above step (1), while increasing the        temperature to the range of 60-150° C., and reacting them        together, wherein the internal electron donors are selected from        the bicycloalkane dicarboxylates or bicycloalkene dicarboxylates        represented by the following formula (III), formula (IV),        formula (V) or formula (VI):

-   -   wherein R₁ and R₂, which may be same or different, are a linear,        branched or cyclic C1-20 alkyl, alkenyl, aryl, arylalkyl or        alkylaryl group, respectively; R₃, R₄, R₅ and R₆, which may be        same or different, are hydrogen, a linear, branched or cyclic        C1-20 alkyl, alkenyl, aryl, arylalkyl or alkylaryl group,        respectively; and    -   (4) reacting the product obtained from the above step (3) with        titanium halide at the temperature of 60-150° C. and washing the        resulted product.

Although the organic solvent used in the above step (1) is notspecifically limited, preferably used may be C6-12 aliphatic, aromaticor halogenated hydrocarbons, more preferably C7-10 saturated aliphatic,aromatic or halogenated hydrocarbons, and for example, at least oneselected from the group consisting of octane, nonane, decane, tolueneand xylene, chlorobutane, chlorohexane, chloroheptane or the like may beused alone or as a mixture.

The dialkoxymagnesium used in the above step (1) which is obtained byreacting metal magnesium with an alcohol anhydride in the presence ofmagnesium chloride is spherical particles having an average particlediameter of 10-200 μm with a smooth surface, and the spherical particleshape is preferably remained as it is even during propylenepolymerization. When the average particle size is less than 10 μm, anincreased amount of microparticles are present in the resulted catalystsand when it is more than 200 μm, bulk density is likely to be smaller,disadvantageously.

The ratio of the organic solvent to dialkoxymagnesium, i.e.dialkoxymagnesium (weight):organic solvent (volume) is preferably1:5-50, more preferably 1:7-20. When the ratio of is less than 1:5,viscosity of the slurry becomes rapidly increased thereby hinderinghomogeneous stirring, and when it is more than 1:50, the bulk density ofthe resulted carrier is significantly reduced or the particle surfacebecomes rough, disadvantageously.

The silane compounds used in the above step (1) may be preferablyrepresented as the following formula (I):Si(OR¹)_(a)R² _((4-a))  (I)

wherein R¹ and R², being independent to each other, are C1-10 alkyl,cyclic alkyl or aryl; when R² is 2 or more, R² may be same or different,a is an integer of 0-4 for the atomic valence.

The specific examples of the silane compounds which may be used include:tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane,tetrabutoxysilane, n-propyltrimethoxysilane, di-n-propyldimethoxysilane,iso-propyltrimethoxysilane, di-iso-propyldimethoxysilane,n-butyltrimethoxysilane, di-n-butyldimethoxysilane,iso-butyltrimethoxysilane, di-iso-butyldimethoxysilane,tert-butyltrimethoxysilane, di-tert-butyldimethoxysilane,n-pentyltrimethoxysilane, di-n-pentyldimethoxysilane,cyclopentyltrimethoxysilane, dicyclopentyldimethoxysilane,cyclopentylmethyldimethoxysilane, cyclopentylethyldimethoxysilane,cyclopentylpropyldimethoxysilane, cyclohexyltrimethoxysilane,dicyclohexyldimethoxysilane, dicyclohexylmethyldimethoxysilane,cyclohexylethyldimethoxysilane, cyclohexyl propyldimethoxysilane,cycloheptyltrimethoxysilane, dicycloheptyldimethoxysilane,cycloheptylmethyldimethoxysilane, cyclheptyldimethoxysilane,cyclheptylpropyldimethoxysilane, phenyltrimethoxysilane,diphenyldimethoxysilane, phenylmethyldimethoxysilane,phenylethyldimethoxysilane, phenylpropyldimethoxysilane,n-propyltriethoxysilane, di-n-propyldiethoxysilane,iso-propyltriethoxysilane, di-iso-propyldiethoxysilane,n-butyltriethoxysilane, di-n-butyldiethoxysilane,iso-butyltriethoxysilane, di-iso-butyldiethoxysilane,tert-butyltriethoxysilane, ditert-butyldiethoxysilane,n-pentyltriethoxysilane, di-n-pentyldiethoxysilane,cyclopentyltriethoxysilane, dicyclopentyldiethoxysilane,cyclopentylmethyldiethoxysilane, cyclopentylethyldiethoxysilane,cyclopentylpropyldiethoxysilane, cyclohexyltriethoxysilane,dicyclohexyldiethoxysilane, cyclohexylmethyldiethoxysilane,cyclohexylethyldiethoxysilane, cyclohexylpropyldiethoxysilane,cycloheptyltriethoxysilane, dicycloheptyldiethoxysilane,cycloheptylmethyldiethoxysilane, cycloheptylethyldiethoxysilane,cycloheptylpropyldiethoxysilane, phenyltriethoxysilane,diphenyldiethoxysilane, phenylmethyldiethoxysilane,phenylethyldiethoxysilane, phenylpropyldiethoxysilane and the like. Asfor the silane compounds, particularly tetraalkoxysilane is preferablyused regarding the effect of improving stereoregularity. Mostpreferably, tetraethoxysilane is used.

The ratio of the silane compounds to the dialkoxymagnesium is preferablyin the range of 0.1-1 moles, based on the 1 mole of dialkoxymagnesium.When the molar ratio is out of said range, the activity of the resultedsolid catalyst or stereoregularity of the resulted polymer may belowered, disadvantageously, and the bulk density of the polymer israpidly reduced or the particle surface become coarse,disadvantageously.

The titanium halides used in the above step (2) of the process forpreparing a solid catalyst according to the present invention may bepreferably represented by the following formula (II):Ti(OR)_(a)X_((4-a))  (II)

wherein, R is a C1-10 alkyl group; X is halogen atom; a is an integer of0-3 for the atomic valence in the above formula (I). Particularly,titanium tetrachloride is preferably used.

The step (2) of the process for preparing a solid catalyst is preferablycarried out by gradually adding titanium halide at a temperature rangeof −20° C.-50° C.

The amount of titanium halide used in the above step (2) is preferably0.1-10 moles, more preferably 0.3-2 moles, based on 1 mole ofdialkoxymagnesium. When the amount is less than 0.1 mole, the conversionof dialkoxymagnesium to magnesium chloride does not smoothly proceed,and when the amount is more than 10 moles, an excessive amount oftitanium components are present in the resulted catalyst,disadvantageously.

In the method for preparing a solid catalyst according to the presentinvention, the internal electron donor used in the said step (3) may berepresented by the following formula (III), formula (IV), formula (V) orformula (VI):

wherein, R₁ and R₂, which may be same or different, are a linear,branched or cyclic C1-20 alkyl, alkenyl, aryl, arylalkyl or alkylarylgroup, respectively; R₃, R₄, R₅ and R₆, which may be same or different,are hydrogen, a linear, branched or cyclic C1-20 alkyl, alkenyl, aryl,arylalkyl or alkylaryl group, respectively.

As for the specific examples of the internal electron donator, thefollowing compounds may be mentioned:bicyclo[2.2.1]heptane-2,3-dicarboxylic acid ethylhexylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid dioctylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid di-iso-butylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid dibutylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid di-iso-propylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid dipropylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid diethylester,bicyclo[2.2.1]heptane-2,3-dicarboxylic acid dimethylester,7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid ethylhexylester,7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dioctylester,7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic aciddi-iso-butylester, 7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylicacid dibutylester, 7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylicacid di-iso-propylester,7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dipropylester,7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid diethylester,7,7-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dimethylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid ethylhexylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dioctylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid di-iso-butylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dibutylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid di-iso-propylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dipropylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid diethylester,5-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dimethylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid ethylhexylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dioctylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid di-iso-butylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dibutylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid di-iso-propylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dipropylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid diethylester,6-methylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dimethylester,5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid ethylhexylester,5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dioctylester,5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic aciddi-iso-butylester, 5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylicacid di-butylester, 5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylicacid di-iso-propylester,5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dipropylester,5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid diethylester,5,6-dimethylbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dimethylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid ethylhexylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dioctylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid di-iso-butylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dibutylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid di-iso-propylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dipropylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid diethylester,bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dimethylester,7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acidethylhexylester, 7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dioctylester, 7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid di-iso-butylester,7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dibutylester,7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic aciddi-iso-propylester,7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic aciddipropylester, 7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid diethylester, 7,7-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dimethylester, 5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid ethylhexylester, 5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dioctylester, 5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid di-iso-butylester,5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid di-butylester,5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic aciddi-iso-propylester, 5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dipropylester, 5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid diethylester, 5-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dimethylester, 6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid ethylhexylester, 6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dioctylester, 6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid di-iso-butylester,6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid di-butylester,6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic aciddi-iso-propylester, 6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dipropylester, 6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid diethylester, 6-methylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dimethylester,5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acidethylhexylester, 5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dioctylester, 5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid di-iso-butylester,5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic aciddi-butylester, 5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid di-iso-propylester,5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic aciddi-propylester, 5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid diethylester, 5,6-dimethylbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylicacid dimethylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acidethylhexylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddioctylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddi-iso-butylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddibutylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddi-iso-propylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddipropylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddiethylester, bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddimethylester, 7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid ethylhexylester,7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acid dioctylester,7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddi-iso-butylester, 7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dibutylester, 7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid di-iso-propylester,7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddipropylester, 7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid diethylester, 7,7-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dimethylester, 5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid ethylhexylester, 5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dioctylester, 5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid di-iso-butylester,5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acid dibutylester,5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddi-iso-propylester, 5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dipropylester, 5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid diethylester, 5-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dimethylester, 6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid ethylhexylester, 6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dioctylester, 6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid di-iso-butylester,6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acid dibutylester,6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddi-iso-propylester, 6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dipropylester, 6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid diethylester, 6-methylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dimethylester,5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acidethylhexylester, 5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dioctylester, 5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid di-iso-butylester,5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acid dibutylester,5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddi-iso-propylester,5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic aciddipropylester, 5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid diethylester, 5,6-dimethylbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylicacid dimethylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acidethylhexylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddioctylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddi-iso-butylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddibutylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddi-iso-propylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddipropylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddiethylester, bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddimethylester, 7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid ethylhexylester,7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddioctylester, 7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid di-iso-butylester,7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddibutylester, 7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid di-iso-propylester,7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddipropylester, 7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid diethylester,7,7-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddimethylester, 5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid ethylhexylester,5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acid dioctylester,5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddi-iso-butylester, 5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid dibutylester, 5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid di-iso-propylester,5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddipropylester, 5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid diethylester, 5-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid dimethylester,6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acidethylhexylester, 6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid dioctylester, 6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid di-iso-butylester,6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acid dibutylester,6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddi-iso-propylester,6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddipropylester, 6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid diethylester, 6-methylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid dimethylester,5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acidethylhexylester, 5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acid dioctylester,5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddi-iso-butylester,5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddibutylester, 5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid di-iso-propylester,5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddipropylester, 5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylicacid diethylester,5,6-dimethylbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddimethylester and the like. It is possible to use the above listedcompounds in the form of a mixture of one or more selected therefrom.

The above step (3) is preferably carried out by while graduallyincreasing the temperature of the product resulted from the step (2) tothe range of 60-150° C., preferably 80-130° C., adding an internalelectron donor mixture thereto and allowing for them to react for 1-3hours. When the temperature is less than 60° C. or the reaction time isless than 1 hour, the reaction can be hardly completed, and when thetemperature is more than 150° C. or the reaction time is more than 3hours, a side-reaction which may occur may lower the polymerizationactivity or stereospecificity of the resulted catalyst.

The temperature or the number of addition of the internal electrondonor, as long as it is added during the temperature increase process,is not specifically limited, and the total amount of the internalelectron donor used is preferably 0.1-1.0 mole based on 1 mole ofdiethoxymagnesium. When the amount is out of said range, thepolymerization activity or stereospecificity of the resulted catalystmay be decreased disadvantageously.

The step (4) of the catalyst preparation process according to thepresent invention is a process in which the product resulted from theabove step (2) is secondarily reacted with titanium halide at thetemperature range of 60-150° C., preferably 80-130° C. The examples oftitanium halide used in this step may include titanium halide having theabove general formula (II).

The reactions at each step of the above solid catalyst preparationmethod are preferably carried out in a reactor equipped with a stirrerfrom which moisture was sufficiently removed, under nitrogen atmosphere.

The solid catalyst prepared by the above method of the present inventionis formed by comprising magnesium, titanium, halogen, silicon and aninternal electron donor, and preferably comprising magnesium 5-40 wt %,titanium 0.5-10 wt %, halogen 50-85 wt %, silicon 2.5-30 wt % and aninternal electron donor 2.5-30 wt % in terms of the catalyst activity.

The solid catalyst of the present invention may be suitably used inpropylene (co)polymerization, and the method for propylene(co)polymerization using the solid catalyst obtained by the presentinvention comprises polymerization of propylene or co-polymerization ofpropylene with other alpha-olefins in the presence of the solidcatalyst, a cocatalyst and an external electron donor.

The solid catalyst may be prepolymerized with ethylene or alpha-olefinsbefore being used as a component of a polymerization reaction.

The prepolymerization reaction may be carried out at a sufficiently lowtemperature under the pressure of ethylene or alpha-olefin, at thepresence of hydrocarbon solvent such as hexane, said catalyst componentand organoaluminum compound such as triethylaluminum. Theprepolymerization by which catalyst particles are surrounded by polymersso as to maintain the catalyst shape, helps improve the polymermorphology after polymerization. The weight ratio of polymers/catalystafter completion of prepolymerization is preferably about 0.1-20:1.

As a cocatalyst component used in the propylene (co)polymerizationmethod of the present invention, organometallic compounds belonging toGroup II or III of the Periodic table of element may be used, forexample alkylaluminum compounds are preferably used. The alkylaluminumcompounds are represented by the following formula (VII):AlR₃  (VII)

wherein, R is a C1-8 alkyl group.

As for the specific examples of such alkylaluminum compounds,trimethylaluminum, triethylaluminum, tripropylaluminum,tributylaluminum, triisobutylaluminum and trioctylaluminum or the likemay be mentioned.

The ratio of the cocatalyst to the solid catalyst component may bevaried depending on a polymerization method used, however the molarratio of the metal element of the cocatalyst to the titanium element inthe solid catalyst component is preferably the range of 1-1000 and morepreferably the range of 10-300. When the molar ratio of the metalelement, for example such as aluminum in the cocatalyst to the titaniumelement in the solid catalyst component is out of said range of 1-1000,the polymerization activity is significantly degraded,disadvantageously.

As for the external electron donor used in the method for propylene(co)polymerization according to the present invention, at least one ofalkoxy silane compounds represented by the following formula (VIII) maybe used:R¹ _(m)R² _(n)Si(OR³)_((4-m-n))  (VIII)

wherein, R¹ and R², which may be same or different, is linear orbranched C1-12 cyclic alkyl or aryl group; R³ is linear or branched,C1-6 alkyl group; m and n is respectively, 0 or 1; and m+n is 1 or 2.

Specific examples of the external electron donor include the followingcompounds, and it may be used alone or as a mixture of one or more:n-propyltrimethoxysilane, di-n-propyldimethoxysilane,isopropyltrimethoxysilane, di-isopropyldimethoxysilane,n-butyltrimethoxysilane, di-n-butyldimethoxysilane,isobutyltrimethoxysilane, di-isobutyldimethoxysilane,tert-butyltrimethoxysilane, di-tert-butyldimethoxysilane,n-pentyltrimethoxysilane, di-n-pentyldimethoxysilane,cyclopentyltrimethoxysilane, dicyclopentyldimethoxysilane,cyclopentylmethyldimethoxysilane, cyclopentylethyldimethoxysilane,cyclopentylpropyldimethoxysilane, cyclohexyltrimethoxysilane,dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane,cyclohexylethyldimethoxysilane, cyclohexylpropyldimethoxysilane,cycloheptyltrimethoxysilane, dicycloheptyldimethoxysilane,cycloheptylmethyldimethoxysilane, cycloheptylethyldimethoxysilane,cycloheptylpropyldimethoxysilane, penyltrimethoxysilane,dipenyldimethoxysilane, penylmethyldimethoxysilane,penylethyldimethoxysilane, penylpropyldimethoxysilane,n-propyltriethoxysilane, di-n-propyldiethylxysilane,isopropyltriethylxysilane, di-isopropyldiethylxysilane,n-butyltriethylxysilane, di-n-butyldiethylxysilane,isobutyltriethylxysilane, di-isobutyldiethylxysilane,tert-butyltriethylxysilane, di-tert-butyldiethylxysilane,n-pentyltriethylxysilane, di-n-pentyldiethylxysilane,cyclopentyltriethylxysilane, dicyclopentyldiethylxysilane,cyclopentylmethyldiethylxysilane, cyclopentylethyldiethylxysilane,cyclopentylpropyldiethylxysilane, cyclohexyltriethylxysilane,dicyclohexyldiethylxysilane, cyclohexylmethyldiethylxysilane,cyclohexylethyldiethylxysilane, cyclohexylpropyldiethylxysilane,cycloheptyltriethylxysilane, dicycloheptyldiethylxysilane,cycloheptylmethyldiethylxysilane, cycloheptylethyldiethylxysilane,cycloheptylpropyldiethylxysilane, penyltriethylxysilane,di-penyldiethylxysilane, penylmethyldiethylxysilane,penylethyldiethylxysilane, penylpropyldiethylxysilane or the like.

The amount of external electron donor may be slightly varied dependingon the polymerization method applied thereto, however the molar ratio ofthe silicon atom in the external electron donor based on the titaniumatom in the catalyst component is preferably in the range of 0.1-500moles and more preferably 1-100. When the molar ratio of the siliconatom in the external electron donor to the titanium atom in the catalystcomponent is less than 0.1, stereoregularity of the propylene polymer issignificantly lowered, disadvantageously, and when it is more than 500,polymerization activity of the catalyst is significantly decreased.

During the propylene polymerization or copolymerization reaction, thepolymerization temperature is preferably 20-120° C. When thepolymerization temperature is less than 20° C., the polymerizationreaction cannot sufficiently proceed, and when it is more than 120° C.,the activity is considerably lowered and the physical properties of theresulted polymers is degraded, disadvantageously.

EXAMPLES

Hereinafter, the present invention is further described through thefollowing example, in detail. However, it should be understood that theexamples are only provided on illustrative purposes without anyintention to limit the scope of the present invention.

Example 1

1. Preparation of Solid catalyst

To a 1 L-volume glass reactor of which atmosphere was sufficientlysubstituted by nitrogen, equipped with a stirrer, 150 ml of toluene and20 g of spherical-shaped diethoxymagnesium having an average particlesize of 20 μm, particle distribution index of 0.86, bulk density of 0.35g/cc were added, and then 2.5 ml of tetraethoxysilane was further addedthereto and allowed to react for 30 minutes while maintaining thetemperature at 10° C. 40 ml of titanium tetrachloride diluted in 60 mlof toluene over 1 hour, and then thereto a mixture ofbicyclo[2.2.1]heptane-2,3-ene-dicarboxylic acid dibutylester 6.6 g wasadded while increasing the reactor temperature to 110° C. Aftermaintaining the temperature at 110° C. for 2 hours and then lowering itto 90° C., stirring was halted; the supernatant was removed; and theresultant was washed once with additional 200 ml toluene. Thereto, 150ml toluene and 50 ml titanium tetrachloride were added, and thetemperature was raised to nor and maintained for 2 hours for aging.After completion of the aging process, the slurry mixture was washedtwice with 200 ml toluene per washing, and then washed 5 times at 40° C.with 200 ml n-hexane per washing, thereby obtaining a pale yellow solidcatalyst component. The obtained catalyst component was dried for 18hours under a nitrogen stream, and the titanium content in the resultedsolid catalyst component was 2.8 wt %.

2. Polypropylene Polymerization

Into a 4 L-volume high-pressure stainless reactor, 10 mg of thusobtained solid catalyst, 6.6 mmol of triethylaluminum and 0.66 mmol ofcyclohexylmethyldimethoxysilane were added. Next, 1000 ml of hydrogenand 2.4 L of liquid propylene were added in this order andpolymerization was carried out at an elevated temperature of 70° C.After 2 hours from the start of polymerization, the remaining propyleneinside the reactor was completely removed by opening the valve, whilelowering the reactor temperature to room temperature.

Analysis of thus resulted polymer was carried out and the results wererepresented in Table 1.

The catlyst activity and stereoregularity were determined by thefollowing method.

-   -   {circle around (1)} Catalyst activity (kg-PP/g-cat)=the amount        of polymers produced (kg)÷the amount of catalyst used (g)    -   {circle around (2)} Stereoregularity (X.I.): the amount of        insolubles crystallized and precipitated in mixed xylene solvent        (wt %)

Example 2

A catalyst was prepared according to the method described in Example 1except that bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dibutylester6.6 g was used instead of bicyclo[2.2.1]heptane-2,3-dicarboxylic aciddibutylester 6.6 g in the above item ‘1. Preparation of solid catalyst’.The titanium content of the resulted solid catalyst component was 2.2 wt%. Next, propylene polymerization was carried out by the same method asin Example 1, and the result was represented in Table 1.

Example 3

A catalyst was prepared according to the method described in Example 1except that bicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acid dibutylester6.6 g was used instead of bicyclo[2.2.1]heptane-2,3-dicarboxylic aciddibutylester 6.6 g in the above item ‘1. Preparation of solid catalyst’.The titanium content of the resulted solid catalyst component was 3.1 wt%. Next, propylene polymerization was carried out by the same method asin Example 1, and the result was represented in Table 1.

Example 4

A catalyst was prepared according to the method described in Example 1except that bicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic aciddibutylester 6.6 g was used instead ofbicyclo[2.2.1]heptane-2,3-dicarboxylic acid dibutylester 6.6 g in theabove item ‘1. Preparation of solid catalyst’. The titanium content ofthe resulted solid catalyst component was 3.1 wt %. Next, propylenepolymerization was carried out by the same method as in Example 1, andthe result was represented in Table 1.

Example 5

A catalyst was prepared according to the method described in Example 1except that bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid diethylester5.3 g was used instead of bicyclo[2.2.1]heptane-2,3-dicarboxylic aciddibutylester 6.6 g in the above item ‘1. Preparation of solid catalyst’.The titanium content of the resulted solid catalyst component was 2.1 wt%. Next, propylene polymerization was carried out by the same method asin Example 1, and the result was represented in Table 1.

Example 6

A catalyst was prepared according to the method described in Example 1except that tetraethoxysilane 5.0 ml was used instead oftetraethoxysilane 2.5 ml in the above item ‘1. Preparation of solidcatalyst’. The titanium content of the resulted solid catalyst componentwas 2.5 wt %. Next, propylene polymerization was carried out by the samemethod as in Example 1, and the result was represented in Table 1.

Comparative Example 1

1. Preparation of Solid Catalyst

To a 1 L-volume glass reactor of which atmosphere was sufficientlysubstituted by nitrogen, equipped with a stirrer, 150 ml of toluene, 12ml of tetrahydrofuran, 20 ml of butanol and 21 g of magnesium chloridewere added, and the temperature was raised to 110° C. and maintained for1 hour, thereby obtaining a homogenous solution. The resulted solutionwas cooled to 15° C., then added with 25 ml titanium tetrachloride, andthen, the reactor temperature was raised to 60° C. over 1 hour. Afteraging for 10 minutes, the mixture was stood still for 15 minute so as toprecipitate the carriers, and the supernatant was removed. To the slurryremained in the reactor, 200 ml toluene was added, and stirring,allowing to stand still and removal of the supernatant was carried outtwice for washing.

To the resulted slurry, 150 ml toluene was added, then 25 ml titaniumtetrachloride diluted in 50 ml toluene was further added at 15° C. over1 hour, and the reactor temperature was elevated to 30° C. at the speedof 0.5° C. per minute. The reaction mixture was maintained at 30° C. for1 hour, 7.5 ml of di-isobutylphthalate was added, and then itstemperature was elevated to 110° C. at the speed of 0.5° C. per minute.

After maintaining the temperature at 110° C. for 1 hour and thenlowering to 90° C., stirring was halted, the supernatant was removed,and the resultant was washed once with additional 200 ml toluene in thesame way. Thereto, 150 ml toluene and 50 ml titanium tetrachloride wereadded, and the temperature was raised to 110° C. and maintained for 1hours for aging. After completion of the aging process, the mixed slurrywas washed twice with 200 ml toluene per washing, and then washed 5times at 40° C. with 200 ml n-hexane per washing, thereby obtaining apale yellow solid catalyst component. The obtained catalyst componentwas dried for 18 hours under a nitrogen stream, and the titanium contentin the resulted solid catalyst component was 3.3 wt %.

2. Polypropylene Polymerization

Polymerization was carried out according to the method described inExample 1 except using the above-obtained solid catalyst 10 mg, and theresult was represented in Table 1.

Comparative Example 2

A catalyst was prepared according to the method described in Example 1except that the process of adding tetraethoxysilane 2.5 ml and allowingit to react for 30 minutes was excluded from the above item ‘1.Preparation of solid catalyst’. The titanium content of the resultedsolid catalyst component was 3.2 wt %. Next, propylene polymerizationwas carried out by the same method as in Example 1, and the result wasrepresented in Table 1.

Comparative Example 3

A catalyst was prepared according to the method described in Example 1except that the process of adding tetraethoxysilane 2.5 ml and allowingit to react for 30 minutes was excluded, andbicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid dibutylester 6.6 g wasused instead of bicyclo[2.2.1]heptane-2,3-dicarboxylic acid dibutylester6.6 g, in the above item ‘1. Preparation of solid catalyst’. Thetitanium content of the resulted solid catalyst component was 3.1 wt %.Next, propylene polymerization was carried out by the same method as inExample 1, and the result was represented in Table 1.

Comparative Example 4

A catalyst was prepared according to the method described in Example 1except that the process of adding tetraethoxysilane 2.5 ml and allowingit to react for 30 minutes was excluded, andbicyclo[2.2.1]hept-2-ene-2,3-dicarboxylic acid dibutylester 6.6 g wasused instead of bicyclo[2.2.1]heptane-2,3-dicarboxylic acid dibutylester6.6 g, in the above item ‘1. Preparation of solid catalyst’. Thetitanium content of the resulted solid catalyst component was 3.2 wt %.Next, propylene polymerization was carried out by the same method as inExample 1, and the result was represented in Table 1.

Comparative Example 5

A catalyst was prepared according to the method described in Example 1except that the process of adding tetraethoxysilane 2.5 ml and allowingit to react for 30 minutes was excluded, andbicyclo[2.2.1]hept-2,5-diene-2,3-dicarboxylic acid dibutylester 6.6 gwas used instead of bicyclo[2.2.1]heptane-2,3-dicarboxylic aciddibutylester 6.6 g, in the above item ‘1. Preparation of solidcatalyst’. The titanium content of the resulted solid catalyst componentwas 3.0 wt %. Next, propylene polymerization was carried out by the samemethod as in Example 1, and the result was represented in Table 1.

TABLE 1 Activity Stereoregularity (kg-PP/g-Cat) (X.I., wt. %) Example 155 98.5 Example 2 40 99.0 Example 3 47 98.1 Example 4 36 98.2 Example 535 99.1 Example 6 48 98.7 Comp. 26 97.3 example 1 Comp. 48 97.6 example2 Comp. 31 98.2 example 3 Comp. 40 97.5 example 4 Comp. 35 97.5 example5

As seen from the above Table 1, Examples 1-6 according to the presentinvention show excellent stereoregularity and catalyst activity by usinga mixture of a silane compound and bicycloalkanedicarboxylates orbicycloalkendicarboxylates as an internal electron donor, whereasComparative example 1 shows significantly low activity andstereoregularity; Comparative example 2, 4 and 5 shows significantly lowstereoregularity; and Comparative example 3 shows lower activity, ascompared to the results of Examples according to the present invention.

INDUSTRIAL AVAILABILITY

By using the solid catalyst prepared by the present invention, it ispossible to prepare polypropylene having excellent stereoregularity witha high production yield.

What is claimed is:
 1. A method for preparing a solid catalyst forpropylene polymerization comprising the following steps: (1) reactingdialkoxy magnesium with silane compounds in the presence of an organicsolvent selected from the group consisting of C6-C12 aliphatichydrocarbons, C6-C12 aromatic hydrocarbons and C6-C12 halogenatedhydrocarbons; (2) reacting titanium halide with the resulted productobtained from the step (1) (3) adding one or more internal electrondonors to the product resulted from the above step (1) while increasingthe temperature to the range of 60-150° C., and reacting them together,wherein the internal electron donors are selected from the bicycloalkanedicarboxylates or bicycloalkene dicarboxylates represented by thefollowing formula (III), formula (IV), formula (V) or formula (VI):

wherein R₁ and R₂, which may be same or different, are a linear,branched or cyclic C1-20 alkyl, alkenyl, aryl, arylalkyl or alkylarylgroup, respectively; R₃, R₄, R₅ and R₆, which may be same or different,are hydrogen, a linear, branched or cyclic C1-20 alkyl, alkenyl, aryl,arylalkyl or alkylaryl group, respectively; and (4) reacting the productobtained from the above step (3) with titanium halide at the temperatureof 60-150° C. and washing the resulted product.
 2. The method forpreparing a solid catalyst for propylene polymerization according toclaim 1, wherein the silane compounds is represented as the followingformula (I):Si(OR¹)_(a)R² _((4-a))  (I) wherein R¹ and R², being independent to eachother, are C1-10 alkyl, cyclic alkyl or aryl; when R² is 2 or more, R²may be same or different, a is an integer of 0-4 for the atomic valence.3. The method for preparing a solid catalyst for propylenepolymerization according to claim 1, wherein the silane compounds istetraalkoxysilane.
 4. The method for preparing a solid catalyst forpropylene polymerization according to claim 1, wherein the silanecompounds is used at the amount of 0.1-1.0 moles based on the 1 mole ofthe dialkoxymagnesium.
 5. The method for preparing a solid catalyst forpropylene polymerization according to claim 1, wherein the internalelectron donor is used at the amount of 0.1-1.0 moles based on the 1mole of the dialkoxymagnesium.